arnyk wrote: > The literature related to doing this kind of listening test contains > many examples of attention and inattention to the potential for > nonlinear distortion (e.g. IM) in the monitoring system to cause false > positives. > > This pair of sample-rate-testing files contain the results of several > generations of trying to build a listening test that is self-diagnostic > for this problem: 'Link to files for studying the audible effects of > downsampling that are also self-diagnostic for IM' > (http://www.hydrogenaud.io/forums/index.php?showtopic=107570&view=findpost&p=894877) > > The way this works is that the primary test is the classic "Keys > Jangling" sound originally recorded at 24/96 and then downsampled to > 44/16 and upsampled back to 24/96. Following the keys jangling sound is > a brief low level marker tone followed by ultrasonic test tones > designed to elicit audible IM if there is excess nonlinear distortion in > the monitoring chain. > > The intent is that an ABX file comparison tool such as Foobar2K with its > ABX plug-in (all freeware) are used to control the test. > > In the basic test (keys jangling, before the audible test tone) the > intent is that you either hear or do not hear a difference. That's the > primary test. > > Following the low level test tone is the secondary qualification test > for your monitoring chain. If you hear any difference between the files > in this test segment, (or hear anything but silence or a very faint low > level rushing noise) then your monitoring chain has audible IM and any > positive results from the primary test are probably the results of that. > IOW, false positives.
Thanks for that Arnold. I'm glad you guys are doing your best to test this properly, as a counter to the somewhat warped methods of those with commercial interests at heart. As an aside, I've recently updated one of my long term projects (involved with genuine ultrasonic content) to take advantage of the ready availability of low cost 192KHz ADC/DAC devices now. I'm really impressed with the performance, but for me - especially with my ageing ears - it is utterly pointless (and quite possibly detrimental) to use such high sample rates for music. ------------------------------------------------------------------------ utgg's Profile: http://forums.slimdevices.com/member.php?userid=40900 View this thread: http://forums.slimdevices.com/showthread.php?t=103537 _______________________________________________ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
